Toner conveying path forming member, toner replenishment unit, and image forming apparatus

Abstract

A toner conveying path forming member forms a toner conveying path with a hollow capable of conveying toner. The toner conveying path forming member includes an inner wall a part of which is pressed by an elastic toner conveying member provided in the toner conveying path; and a protrusion that is provided on an inner wall surface of at least a part of the inner wall to protrude toward the hollow.

What is claimed is: 
     
       1. A toner conveying path forming member including a hollow configured to convey toner, the toner conveying path forming member comprising:
 a protrusion on part of an inner wall of the toner conveying path forming member configured to be pressed by an elastic toner conveying member, the protrusion configured to protrude toward the hollow, wherein
 the toner conveying path forming member includes a curved portion, and 
 the part of the inner wall having the protrusion thereon is a small radius curvature of the curved portion. 
 
 
     
     
       2. The toner conveying path forming member according to  claim 1 , further comprising:
 a first linear portion coupled to the curved portion on an upstream side in the toner conveying direction; and 
 a second linear portion coupled to the curved portion on a downstream side in the toner conveying direction, wherein
 a first protrusion on an inner wall surface of the curved portion at the side of a smaller radius curvature closer to a center of curvature of the curved portion, 
 a second protrusion on an inner wall surface of the first linear portion extending from an inner wall surface of the curved portion at the side of a larger radius curvature further from the center of curvature, and 
 a third protrusion on an inner wall surface of the second linear portion extending from the inner wall surface of the curved portion at the side of the larger radius curvature. 
 
 
     
     
       3. The toner conveying path forming member according to  claim 1 , further comprising:
 a first curved portion at which a center line of the toner conveying path forming member that passes through a center of a hollow section perpendicular to a toner conveying direction is bent; and 
 a second curved portion at which the center line of the toner conveying path forming member is bent to the opposite side from the first curved portion, the second curved portion being arranged on a downstream side of the first curved portion in the toner conveying direction, wherein 
 a first protrusion on an inner wall surface of the first curved portion at the side of a smaller radius curvature closer to a center of curvature of the first curved portion, and 
 a second protrusion on an inner wall surface of the second curved portion at the side of the smaller radius curvature closer to a center of curvature of the second curved portion. 
 
     
     
       4. The toner conveying path forming member according to  claim 1 , further comprising:
 a first curved portion at which a center line of the toner conveying path forming member that passes through a center of a hollow section perpendicular to a toner conveying direction is bent; 
 a first linear portion coupled to the first curved portion on an upstream side in the toner conveying direction; 
 a second curved portion at which the center line of the toner conveying path forming member is bent to the opposite side from the first curved portion, the second curved portion being arranged on a downstream side of the first curved portion in the toner conveying direction; and 
 a second linear portion coupled to the second curved portion on a downstream side in the toner conveying direction, wherein 
 a first protrusion on an inner wall surface of the first curved portion at the side of a smaller radius curvature closer to a center of curvature of the first curved portion, 
 a second protrusion on an inner wall surface of the second curved portion at the side of a smaller radius curvature closer to a center of curvature of the second curved portion, 
 a third protrusion on an inner wall surface of the first linear portion extending from an inner wall surface of the first curved portion at the side of a larger radius curvature further from a center of curvature of the first curved portion, and 
 a fourth protrusion on an inner wall surface of the second linear portion extending from an inner wall surface of the second curved portion at the side of a larger radius curvature further from a center of curvature of the second curved portion. 
 
     
     
       5. The toner conveying path forming member according to  claim 1 , wherein the toner conveying path forming member is a toner housing container. 
     
     
       6. The toner conveying path forming member according to  claim 1 , wherein the protrusion has a circular arc outline in a cross section perpendicular to a toner conveying direction of the toner conveying path forming member. 
     
     
       7. A toner conveying path forming member including a hollow configured to convey toner, the toner conveying path forming member comprising:
 a plurality of protrusions on a curved part of an inner wall of the toner conveying path forming member that is configured to be pressed by an elastic toner conveying member, the protrusions configured to protrude toward the hollow. 
 
     
     
       8. A toner replenishment unit comprising:
 the toner conveying path forming member according to  claim 1 , wherein
 the toner conveying path forming member is configured to convey toner to be supplied to a developing unit. 
 
 
     
     
       9. An image forming apparatus comprising:
 the toner replenishment unit according to  claim 8 ; and 
 a hopper configured to temporarily hold the toner. 
 
     
     
       10. A pipeline having an elastic conveying coil running therethrough, the elastic conveying coil configured to convey toner, the pipeline comprising:
 a protrusion on an inner wall of a non-linear portion of the pipeline in a region that a gravitational force drives the conveying coil in a first direction toward the inner wall, the protrusion configured to contact the conveying coil and force the conveying coil in a second direction different from the first direction. 
 
     
     
       11. The pipeline of  claim 10 , wherein the protrusion is configured to reduce a portion of a surface area of the elastic conveying coil that contacts the pipeline.